OFDM systems with CPM mappers for smart grid applications

Abstract

Smart grid can be thought of as a network of interconnected wireless networks. In such a network, critical reports generated at the customer sites are required to be communicated to a control station through several layers of wireless networks. Communication in these sub-networks is typically achieved using IEEE 802.11 technology that uses Orthogonal Frequency Division Multiplexing (OFDM). Conventionally, in an OFDM system BPSK, QPSK and QAM mappers are used. In this paper, Continuous Phase Modulation (CPM) mapper in an OFDM system is proposed: i) to enhance the physical layer reliability through the introduction of correlation among the transmitted OFDM symbols; and ii) to reduce the Peak-to-Average Power Ratio (PAPR) of transmitted OFDM symbols. The objective, over here is to examine the PAPR performance of OFDM systems with CPM mappers with and without Selective Mapping (SLM) technique. Simulations show that CPM mapper in OFDM systems can provide better PAPR performance compared to conventional mappers used in the existing IEEE 802.11 standards. It is noted that CPM mapper in OFDM is very effective in reducing PAPR and can be easily adopted in 802.11 standards for wireless network communications in smart grid.